Blackberry plant named &#39;A-1960&#39;

ABSTRACT

Description and specifications of a new and distinct blackberry cultivar named ‘A-1960’ which originated from seed produced by a hand pollinated cross of Ark. Selection Ark.-1583 (non-patented, unreleased genotype; female)×Ark.-1482 (non-patented, unreleased genotype; male) is provided. This new blackberry cultivar can be distinguished by its very firm fruit with long shape, medium-large size, attractive fruit appearance, very good flavor, excellent plant health, and cane erectness.

LATIN NAME

Rubus subgenus Rubus Watson

BACKGROUND

The new floricane-fruiting cultivar of blackberry called ‘A-1960’ isdescribed herein. The new cultivar originated from a hand-pollinatedcross of Ark. selections Ark.-1583×Ark.-1482 made in 1991. The seedsresulting from this controlled hybridization were germinated in agreenhouse in the spring of 1992 and planted in a field nearClarksville, Ark. (West-Central Arkansas). The seedlings fruited in thesummer of 1994. One seedling, designated A-1960, was selected in 1994for its very firm fruit with long shape, medium-large size, attractivefruit appearance, very good flavor, excellent plant health, and caneerectness.

SUMMARY OF THE INVENTION

The new and distinct cultivar of blackberry originated from ahand-pollinated cross of Ark. Selection Ark.-1583 (non-patented,unreleased genotype; female)×Ark.-1482 (non-patented, unreleasedgenotype; male) made in 1991 and located near Clarksville, Ark.(West-Central Arkansas). The botanical designation of the new cultivarof blackberry is Rubus subgenus Rubus Watson.

The seeds resulting from this controlled hybridization were germinatedin a greenhouse in the spring of 1992 and planted in a field nearClarksville, Ark. The seedlings fruited in the summer of 1994 onfloricanes. One seedling, designated A-1960, was selected in 1994 forits very firm fruit with long shape, medium-large size, attractive fruitappearance, very good flavor, excellent plant health, and caneerectness.

During 1994, the original plant selection was propagated asexually fromroot cuttings at the above-noted location, and a test row of 10 plantswas established. Subsequently, larger test plantings have beenestablished with asexually multiplied plants at two locations inArkansas. At each location propagation was from root cuttings from theClarksville, Ark. test plot.

The new cultivar has been asexually multiplied since 1994 by the use ofroot cuttings and by rooting adventitious shoots from root cuttings. Itforms new shoots from adventitious buds on root cuttings readily. Duringall asexual multiplication, the characteristics of the original planthave been maintained and no aberrant phenotypes have appeared.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying photographs show typical specimens of the new varietyin color as nearly true as it is reasonably possible to make in a colorillustration of this character.

FIG. 1 is a photograph of blackberry canes of A-1960 taken nearClarksville, Ark.

FIG. 2 is a photograph of ripe fruit on the plant of A-1960.

FIG. 3 is a photograph of ripe fruit of A-1960 cut horizontally andlongitudinally.

FIG. 4 is a photograph showing the abaxial (left) and adaxial (right)sides of a primocane leaf of A-1960.

DETAILED DESCRIPTION OF THE NEW CULTIVAR A-1960

Plants and fruit of this new cultivar differ phenotypically from itsparents. The new cultivar is later ripening and sweeter than parentA-1583, and later ripening, more even drupelet set and is larger thanparent A-1482. Although blackberries (Rubus subgenus Rubus Watson) arehighly heterogeneous and outcrossing, and most clones contain genes frommore than one species, the new cultivar and its progenitor linesphenotypically exhibit characters predominately of the erect easternUnited States species, Rubus allegheniensis Porter (highbushblackberry).

Plants of the new cultivar are vigorous and prolific and rowestablishment following planting is rapid. Both primocanes andfloricanes are erect in growth habit. The canes can be trained to aself-supporting hedgerow although it is beneficial to use a trellis withsupporting wires to prevent canes from falling over due to wind or heavyfruit loads. The plants are thornless. Plants and fruit are moderatelyresistant to anthracnose [Elsinoe veneta (Burkh.) Jenkins], and plantsappear immune to orange rust [Gymnoconia nitens (Schwein.) F. Kern andH. W. Thurston.]. No screening has been done for resistance to doubleblossom/rosette [Cercosporella rubi (Wint.) Plakidas]

The bloom period of the new cultivar begins on average 23 April for 10%bloom and 27 April for 50% bloom. This is two days earlier than forApache (U.S. Plant Pat. No. 11,865) and the same as Ouachita (U.S. PlantPat. No. 17,162).

Floricane fruit of the new cultivar begins ripening 4 days beforeOuachita and about 7 days before Apache and ends about the same time asOuachita. Average first ripening date is 6 June in West-CentralArkansas. The average floricane fruiting period is 40-50 days.

Fruit yields of the new cultivar on floricanes are usually 1.5 to 2.0 kg(3 to 4.5 lb/plant), comparable to Ouachita, in West-Central Arkansas.

The fruit is elongated to slightly conical in shape, black in color, andvery attractive. The floricane fruit is medium-large (5-6 g) similar toOuachita. Fruit size of the new cultivar is maintained well throughoutthe entire harvest season.

The fresh fruit rates very well in flavor, comparable to Ouachita andApache. The soluble solids concentration averages about 11-12% on shinyblack fruit comparable to Apache and Ouachita. Fruit and flower clustersare medium-large, cymose, and are mostly borne on the periphery of theplant canopy, providing easy access to harvest. Flower fertility is highand clusters are well filled.

The following is a detailed description of the botanical and pomologicalcharacteristics of the subject blackberry. Color data are presented inRoyal Horticultural Society Colour Chart designations (1986 2ndedition). Where dimensions, sizes, colors, and other characteristics aregiven, it is to be understood that such characteristics areapproximations of averages set forth as accurately as practicable.

Plants used for botanical data were 16 years old and grown on a finesandy loam soil with sprinkler irrigation near Clarksville, Ark. Theplants were fertilized near budbreak (late March on average) withcomplete or nitrogen fertilizer, and had an additional nitrogenfertilizer application in early July. Primocanes were tipped atapproximately 45 inches, and grown in a hedgerow training system. Weedswere controlled with pre- and post-emergence herbicides supplementedwith mechanical weed control activities. A single application of liquidlime sulfur was applied to the plants at budbreak, but no otherfungicides were used. The descriptions reported herein are fromspecimens grown near Clarksville, Ark.

-   Plant:    -   -   Size.—Plants are grown in a hedgerow and primocanes tipped            at approximately 45 inches; plants in this system then range            in size from about 45 to 55 inches tall and approximately            24-36 inches wide at the top.        -   Growth habit.—Moderate vigor, canes erect; suckers from            crown and roots.        -   Growth rate.—First emergence of primocanes is 24 March and            primocanes reach tipping height (107 cm) on 31 May.        -   Productivity.—Floricane — between 1.5 and 2 kg (slightly            over 4.45 lb/plant), comparable to Ouachita.        -   Cold hardiness.—Hardy to 8° (−13° C.) or lower comparable            Ouachita.        -   Canes.—Thornless, erect. Floricane (dormant or winter cane):            Cane diameter: base 1.40 cm; midpoint 1.11 cm; terminal            0.55 cm. Internode length: base 9.31 cm; midpoint 5.14 cm;            terminal 1.63 cm. Floricane color: base Greyed Orange Group            (166A); midpoint Greyed-Purple Group (185A) over Green Group            (137B); terminus Greyed-Purple Group (185A) over Green Group            (137C). Primocane (current-season cane): Cane diameter: base            1.65 cm; midpoint 1.20 cm; terminal 0.88 cm. Internode            length: base 4.34 cm; midpoint 6.10 cm; terminal 3.11 cm.            Primocane color: base Red Group (46A) over Green Group            (139B); midpoint Red Group (46A) over Green Group (141C);            terminus Red Group (46A) over Yellow-Green Group (146B).            Date of primocane emergence: 24 March.        -   Disease resistance.—Moderate resistance to anthracnose, and            plants appear immune to orange rust. No screening has been            done for resistance to double blossom/rosette.-   Foliage:    -   -   Primocane.—        -   Leaves.—medium; mature compound leaf width 16.06 cm; length            11.18 cm.        -   Leaflet.—Width 6.36 cm; length 8.98 cm; shape round to            slightly elongated with acuminate apex and round, slightly            flat base; margin doubly serrated, serration teeth length            0.16 cm and width 0.24 cm; pubescence is very light on            abaxial and adaxial surfaces; number of leaflets per            compound leaf 5.        -   Color.—Base abaxial Yellow-Green Group (146A); adaxial Green            Group (139A); midpoint abaxial Yellow-Green Group (146A);            adaxial Green Group (139A); terminal abaxial Yellow-Green            Group (146C); adaxial Green Group (137A).        -   Petioles.—Length: 6.12 cm; color: Red Purple Group (60A)            over Yellow Green Group (144A); texture: smooth.        -   Petiolules.—Length: 1.38 cm; color: Red Purple Group (60A)            over Yellow Green Group (144A); texture: smooth.        -   Stipules.—Length: 0.83 cm; width: 0.06 cm; color: Green            Group (137C); texture: smooth.        -   Floricane.—        -   Leaves.—Medium; mature compound leaf width 11.74 cm; length            8.73 cm.        -   Leaflet.—Width 6.43 cm; length 7.00 cm; shape round,            slightly elongated with acuminate apex and rounded base;            margin double serrated, with serration teeth length 0.25 cm            and width at base 0.34 cm; pubescence is lightly present on            abaxial and adaxial sides. Number of leaflets per compound            leaf is 3 most commonly but occasionally up to 5.        -   Color.—base abaxial Green Group (130A); adaxial Green Group            (135A); midpoint abaxial Green Group (137C); adaxial Green            Group (132A); terminal abaxial Green Group (137A); adaxial            Green Group (139A).        -   Petioles.—Length 5.20 cm; color: Green Group (139B) texture:            smooth.        -   Petiolules.—Length 0.40 cm; color: Green Group (139B);            texture: smooth.        -   Stipules.—Length 0.63 cm; width: 0.13 cm; color: Green Group            (137C); texture: smooth.-   Flowers:    -   -   Floricane.—        -   Date of bloom.—23 April for 10% bloom and 27 April for 50%            bloom; two days earlier than for Apache and the same as            Ouachita.        -   Petal color.—Red Purple Group (65D).        -   Reproductive organs.—Stamens — erect, numerous. Pistils —            numerous. Pollen — normal, fertile, and abundant.        -   Flower diameter.—3.6 cm.        -   Petal size.—Length 1.6 cm; width 1.3 cm.        -   Average number flowers per cluster.—3.        -   Average number of petals per flower.—7.        -   Number of sepals per flower.—5.        -   Peduncle length.—1.1 cm.        -   Peduncle color.—Yellow-Green Group (144A).        -   Cyme type.—Elongate simple cyme.-   Fruit:    -   -   Floricane.—        -   Maturity.—average first ripe 4 days before Ouachita and            about 7 days before Apache and ends about the same time as            Ouachita. Average first ripening date is 6 June in            West-Central Arkansas. The average floricane fruiting period            is 40-50 days.        -   Size.—medium-large, average 5-6 g.        -   Diameter of fruit at primary position on            inflorescence.—equator 2.03 cm; base pole 1.41 cm; terminal            pole 1.22 cm.        -   Diameter of fruit at secondary positions on            inflorescence.—equator 1.86 cm; base pole 1.46 cm; terminal            pole 1.09 cm.        -   Length (primary fruit).—2.68 cm.        -   Shape.—elongated to slightly conical.        -   Color.—Black Group (202A).        -   Drupelet size.—0.47 cm.        -   Seed.—average length 3.94 mm, width 2.10 mm; dry weight 4.11            mg.        -   Soluble solids.—11-12%.        -   pH.—3.19.        -   Acidity.—1.46 g/100 ml expressed as citric acid.        -   Processed quality.—Not evaluated for processing.        -   Uses.—home garden and fresh market use are primary intended            uses due to posttharvest handling potential is not as good            as many other thornless cultivars developed for the shipping            market.-   The cultivar: The most distinctive features of the cultivar are very    firm fruit with long shape, medium-large size, attractive fruit    appearance, very good flavor, excellent plant health, and cane    erectness.

We claim:
 1. A new and distinct cultivar of blackberry plant named‘A-1960,’ substantially as illustrated and described herein.